When it comes to office suites, collaboration can mean different things. iWork, Office, and Google Docs all offer the ability for multiple users to work on a single document with features for adding comments to specific text or other data as well as tracking changes made by each user.

In the case of iWork, both track changes and comments will interoperate very well with the same features in Office. By contrast Google Docs track changes and version history features are not compatible with either Office or iWork.

At this point, this is the limit to major collaborative options in Office. Although functional, these features require that a document either be saved in a shared file space (such as a file server) or moved from one computer to another (via email, external disk, or Internet-based storage) in order for another user to view and edit the file. If the second user makes changes, the updated version must then be returned to the original user in order for him or her to view the changes or comments and make additional edits.

Google Docs, on the other hand, is an online tool. This means that you can share a document with any other user. That user can simply view the document online, make changes or comments, and save the updated document. In order to view their additions, all you need to do is access Google Docs through your account on any computer (the iPhone/iPod Touch is supported but currently in a read-only fashion). Google will also maintain a version history for each document, allowing you to view or retrieve a previous version with little effort.

Sitting in the middle of these two extremes is iWork.com, a new web-based feature that Apple introduced in beta along with iWork 09. iWork.com allows you to publish any iWork document to a shared Internet storage space using an Apple ID (such as the account you use for iTunes Store purchases). When publishing, you can email invitations to other users to access the document using a web browser.

iWork.com displays full formatting of any document through todays common web browsers. When users access a document, they can see who else is accessing it as well as add comments directly to portions of the documents or general notes about the document as a whole, which all other users can see. If you allow, users can download the document in iWork, Office, or PDF formats.

iWork.com is a great first step for Apple in terms of web- or cloud-based collaboration. It offers complete online viewing and commenting as well as complete formatting (rather than the limited formatting available in Google Docs).

The problem is that it doesnt allow online editing. Users (including the owner) cannot make changes to a published document. They can download the document, make changes, and re-publish it, but each time a document is re-published it is treated as a separate document. This presents a massive version control issue as there is no easy way to track different revisions of a single document across user accounts. The problem extends not just to edits, but to comments and notes added to each varying revision.

So, its a tough call for which solution is the best collaborative tool. Google gets high marks for online editing, but at the expense of extensive features available in the other suites and at the requirement that collaborative features are largely limited to Google Docs.

iWork.com works great for sharing documents and receiving feedback and notes, but falls short on actually allowing multiple users to easily work on a single document.

iWork and Office both get high marks for offline editing and collaboration, but require a bit of work or some form or shared space for actually sharing document files.

Overall: Apple iWork vs. Microsoft Office vs. Google Docs

In the overall scheme of things, the choice between iWork, Office, and Google Docs comes down to what you need and are comfortable using. iWork provides a host of innovative features and is great for consumers, small businesses, and users not satisfied with the Office interface or its lack of media integration. Its ability to interoperate with Office makes it a perfectly functional alternative even if you need to collaborate with Office users. Anyone even remotely curious should check out the free trial version.

Users familiar with Office and comfortable with its feature set and interface will probably be most comfortable sticking with it. This is particularly true for users that spend a large amount of time in Excel. However, with its relatively low price tag, iWork can make a good complement to Office even if youre not looking to replace Office completely (like if you want to just replace PowerPoint with Keynote).

Google Docs is ironically the lowest cost (free) option and the one that can easily be accessed from any Mac or PC. However, it is also the most constrained as far as features, formatting options, and interface. While a useful complement to either iWork or Office, its hard to envision Google Docs as a complete solution for many users.